1. Field of the Invention
This invention relates to umbrellas and in particular to means for preventing undesirable blowout or reversal of the open umbrella configuration as from high winds or the like.
2. Description of the Background Art
The problem of blowout or undesirable reversal of the concave configuration of an umbrella due to high winds or the like acting outwardly thereagainst has long been a vexatious problem. Thus, as shown in Hadfield U.S. Pat. No. 559,577, one solution to this problem attempted in the prior art was to provide a spring acting between cords connected at one end to a sleeve on the umbrella shaft, and at the other end to the outer ends of the umbrella ribs, and to the rigid ribs extending from the shaft to the midportion of the resilient ribs for holding the umbrella in the open position. The springs are arranged to be selectively operable to urge the boat configuration to one of greater tension so as to strengthen the ribs in windy or stormy weather. In normal weather, the tension springs are relieved so as to pay out the control cords along the ribs to return to the normal position. The tension springs provide a supplemental resilient force for urging the umbrella to a more deeply concave configuration when desired.
In U.S. Pat. No. 773,499 of D. Hirsch et al, an umbrella is disclosed wherein a coil spring is provided on the umbrella shaft for similarly urging the tension cords resiliently so as to resist turning of the umbrella inside out.
Hans Wagner shows, in U.S. Pat. No. 1,093,160, an umbrella structure having bands employed as stiffeners acting between the center stick of the umbrella, which is offset from the main support post thereof, and the center portion of the ribs.
Herman J. Raabe shows, in U.S. Pat. No. 1,167,431, an umbrella construction having reinforcing rods connected between the resilient ribs and rigid ribs of the umbrella.
In U.S. Pat. No. 2,522,645, Salvatore M. Senna shows an umbrella having means for reinforcing the ribs comprising a flexible member made of wire, nylon strand, or braid, or other flexible material resistant to stretching. The connector extends from a first connection adjacent the distal end of the resilient ribs through an eye carried on the post of the umbrella and to a second connector adjacent the inner end of the resilient ribs. Each of the ends of the flexible connector is fixedly connected to its associated eye by tying or by a clip secured to the ends of the connector.
Ovaldo Wendorf discloses, in U.S. Pat. No. 3,032,047, a storm umbrella having a plurality of beaded chain or cords made of fiberglass, nylon, or the like, fixedly connected between the distal ends of the resilient bowed ribs and a connector on the umbrella shaft.